This invention relates to novel complexes of technetium (Tc), containing the moiety Tcxe2x95x90NR, Tcxe2x80x94Nxe2x95x90NY or Tc(xe2x80x94Nxe2x95x90NY)2, and their use in radiopharmaceuticals for a variety of clinical applications. Methods for the preparation of the technetium complexes are also described.
Radiopharmaceuticals may be used as diagnostic or therapeutic agents by virtue of the physical properties of their constituent radionuclides. Thus, their utility is not based on any pharmacologic action. Most clinically used drugs of this class are diagnostic agents incorporating a gamma-emitting nuclide which, because of physical or metabolic properties of its co-ordinated ligands, localises in a specific organ after intravenous injection. The resultant images can reflect organ structure or function. These images are obtained by means of a gamma camera that detects the distribution of ionising radiation emitted by the radioactive molecules. The principal isotope currently used in clinical diagnostic nuclear medicine is metastable technetium-99m (99mTc) and which has a half-life of 6 hours.